Ratchet wrenches are well known. Most ratchet wrenches utilize a socket, where the socket includes an opening formed in the shape of a specific fastener size, for example, a half inch hexagonal bolt or a 14 mm twelve point bolt head. Most ratchet wrenches are sold with a variety of sockets, each socket designed to fit a specific sized bolt or nut.
In such wrenches, the wrench includes structure adapted to secure the socket to a ratchet mechanism such that a variety of sockets may be interchangeably attached to the wrench. In recent years, ratchet wrenches and sockets have been standardized where the ratchet wrench includes a protruding shank that is ⅜ inch square and the socket has a ⅜ inch square opening to accommodate the shank. Another standard size ratchet wrench shank is ½ inch square with the sockets having corresponding ½ inch square openings.
Typically, a ratchet wrench selectively allows the socket to rotate freely in one direction, but inhibits rotation in the reverse direction so that as a bolt is tightened or loosened, the wrench does not need to be removed from the bolt. Open end wrenches have been used for over a century. Open end wrenches typically have a U-shaped opening at one end with opposed parallel faces that are manufactured to fit one single bolt or nut size. Open end wrenches allow a technician or handyman to engage a bolt or nut when only a radial face of the bolt or nut is exposed. A drawback to an open end wrench is that the user must constantly remove the wrench from the bolt or nut and reposition the wrench in order to tighten or loosen the bolt or nut.